serious Emtb build questions

[ev7]

Hey everyone, greetings from western Canada!

First post. I read the rules and did a search here and found no recent info for a similar build. One that was recent and close but got no responses..

If someone wants to help that would be awesome!

I'm looking to make something that can sortof keep up with my friends talaria, not looking to compete. Just want to be able to ride the trails without him having to wait too long for and being able to lift it over fences would be great come hunting season.

So I'm thinking of getting an older DH bike or a freeride enduro style to save some weight if the rear triangle can handle it and then putting a bbshd on it. I got pretty good at pedalling with a wrist throttle so I don't really care about torque sensing. I like power to climb big challenging hills but I prefer range that having all out power. The cyc seems good but power hungry, loud and expensive.

So I guess I'm curious of you can help me determine controllers, donor bike, and driveline upgrade components. Or if you think I should wait on a new motor to come out or get something different. Oh I'd also like to build my own battery if that's worth it in your opinions. .


Thanks for the help!

 

[Nix Liou]

Hey everyone, greetings from western Canada!

First post. I read the rules and did a search here and found no recent info for a similar build. One that was recent and close but got no responses..

If someone wants to help that would be awesome!

I'm looking to make something that can sortof keep up with my friends talaria, not looking to compete. Just want to be able to ride the trails without him having to wait too long for and being able to lift it over fences would be great come hunting season.

So I'm thinking of getting an older DH bike or a freeride enduro style to save some weight if the rear triangle can handle it and then putting a bbshd on it. I got pretty good at pedalling with a wrist throttle so I don't really care about torque sensing. I like power to climb big challenging hills but I prefer range that having all out power. The cyc seems good but power hungry, loud and expensive.

So I guess I'm curious of you can help me determine controllers, donor bike, and driveline upgrade components. Or if you think I should wait on a new motor to come out or get something different. Oh I'd also like to build my own battery if that's worth it in your opinions. .


Thanks for the help!

The BBSHD has an integrated controller. People mod the BBSHD with an upgraded gear and a third party controller sometimes to push more power, but it gets a good amount more involved. The ASI BAC 855 is fairly common for that, iirc.

You are going to have difficulty keeping up in terms of range and power within a normal bike frame, especially a frame with a rear suspension setup. The available triangle space will be fairly limiting, even with a custom battery design to fit the frame perfectly. You can look for an older style bike frame that doesn't have a hydroformed frame (characteristic curvy lines, vs simple straight tubes for the frame).

I agree that the CYC is not the best option, but "power hungry" doesn't really matter- these mid drive motors are all going to be comparable efficiency, meaning more power use is more power to the wheels, and you can always run at a lower power level. The CYC motor rating is not a continuous rating, and it will generally throttle itself after a couple minutes of intensive riding at that power level.

Do you have a ballpark number for the range you want? Trail riding tends to be pretty energy intensive, especially the faster you go and the more power you have. When you increase the power and torque, you increase the load and stress on the chain significantly, and you should expect to wear through cassettes and chains a lot faster.

The most precise and involved part of this build will be the battery if you go DIY. You will need a battery spot welder (and not a cheap garbage one) and probably a pretty robust soldering iron. A multimeter is pretty useful for checking your work as you build, and a cell tester for IR is useful for matching cells but isn't necessary with new cells from a reputable brand.
On top of the tools you will need quality cells, of which there are a variety of options depending on your needs, a robust battery management system, capable bus bars, wiring, connectors, cell spacers, insulation, waterproofing, a case, etc.
Making one dumb mistake during much of the build process can be catastrophic if you are not properly respecting the dangers.
But if you are willing to take your time and do it right you can get a high quality result and save hundreds, and learn many new skills.

Overall, I think the BBSHD is probably a pretty solid and robust option here if you don't need torque sensing and want good torque. To come close to optimizing the battery capacity you will need something custom, and it's probably cheaper to build it yourself, even with buying proper equipment for a pack like this. I am a big proponent of DIY batteries due to the current state of the consumer li-ion battery pack market, but there are lots of things you can do wrong if you don't do your research.

 

[phobos]

I think you should go for either @LightningRods small block or big block. Small block is a step above BBSHD, power is equivalent to a stock Surron, big block is at the 72V Surron power level.

 

[Nix Liou]

I think you should go for either @LightningRods small block or big block. Small block is a step above BBSHD, big block is at the 72V Surron power level.

Agreed, this would be my recommendation for keeping up with a Talaria, but it's enough power and capability to require a beefy frame, and it definitely goes over the threshold into needing an expensive battery as well. A big step up in power and cost.

 

[ev7]

The BBSHD has an integrated controller. People mod the BBSHD with an upgraded gear and a third party controller sometimes to push more power, but it gets a good amount more involved. The ASI BAC 855 is fairly common for that, iirc.

You are going to have difficulty keeping up in terms of range and power within a normal bike frame, especially a frame with a rear suspension setup. The available triangle space will be fairly limiting, even with a custom battery design to fit the frame perfectly. You can look for an older style bike frame that doesn't have a hydroformed frame (characteristic curvy lines, vs simple straight tubes for the frame).

I agree that the CYC is not the best option, but "power hungry" doesn't really matter- these mid drive motors are all going to be comparable efficiency, meaning more power use is more power to the wheels, and you can always run at a lower power level. The CYC motor rating is not a continuous rating, and it will generally throttle itself after a couple minutes of intensive riding at that power level.

Do you have a ballpark number for the range you want? Trail riding tends to be pretty energy intensive, especially the faster you go and the more power you have. When you increase the power and torque, you increase the load and stress on the chain significantly, and you should expect to wear through cassettes and chains a lot faster.

The most precise and involved part of this build will be the battery if you go DIY. You will need a battery spot welder (and not a cheap garbage one) and probably a pretty robust soldering iron. A multimeter is pretty useful for checking your work as you build, and a cell tester for IR is useful for matching cells but isn't necessary with new cells from a reputable brand.
On top of the tools you will need quality cells, of which there are a variety of options depending on your needs, a robust battery management system, capable bus bars, wiring, connectors, cell spacers, insulation, waterproofing, a case, etc.
Making one dumb mistake during much of the build process can be catastrophic if you are not properly respecting the dangers.
But if you are willing to take your time and do it right you can get a high quality result and save hundreds, and learn many new skills.

Overall, I think the BBSHD is probably a pretty solid and robust option here if you don't need torque sensing and want good torque. To come close to optimizing the battery capacity you will need something custom, and it's probably cheaper to build it yourself, even with buying proper equipment for a pack like this. I am a big proponent of DIY batteries due to the current state of the consumer li-ion battery pack market, but there are lots of things you can do wrong if you don't do your research.

anks for the reply!

The BBSHD has an integrated controller. People mod the BBSHD with an upgraded gear and a third party controller sometimes to push more power, but it gets a good amount more involved. The ASI BAC 855 is fairly common for that, iirc.

You are going to have difficulty keeping up in terms of range and power within a normal bike frame, especially a frame with a rear suspension setup. The available triangle space will be fairly limiting, even with a custom battery design to fit the frame perfectly. You can look for an older style bike frame that doesn't have a hydroformed frame (characteristic curvy lines, vs simple straight tubes for the frame).

I agree that the CYC is not the best option, but "power hungry" doesn't really matter- these mid drive motors are all going to be comparable efficiency, meaning more power use is more power to the wheels, and you can always run at a lower power level. The CYC motor rating is not a continuous rating, and it will generally throttle itself after a couple minutes of intensive riding at that power level.

Do you have a ballpark number for the range you want? Trail riding tends to be pretty energy intensive, especially the faster you go and the more power you have. When you increase the power and torque, you increase the load and stress on the chain significantly, and you should expect to wear through cassettes and chains a lot faster.

The most precise and involved part of this build will be the battery if you go DIY. You will need a battery spot welder (and not a cheap garbage one) and probably a pretty robust soldering iron. A multimeter is pretty useful for checking your work as you build, and a cell tester for IR is useful for matching cells but isn't necessary with new cells from a reputable brand.
On top of the tools you will need quality cells, of which there are a variety of options depending on your needs, a robust battery management system, capable bus bars, wiring, connectors, cell spacers, insulation, waterproofing, a case, etc.
Making one dumb mistake during much of the build process can be catastrophic if you are not properly respecting the dangers.
But if you are willing to take your time and do it right you can get a high quality result and save hundreds, and learn many new skills.

Overall, I think the BBSHD is probably a pretty solid and robust option here if you don't need torque sensing and want good torque. To come close to optimizing the battery capacity you will need something custom, and it's probably cheaper to build it yourself, even with buying proper equipment for a pack like this. I am a big proponent of DIY batteries due to the current state of the consumer li-ion battery pack market, but there are lots of things you can do wrong if you don't do your research.

Thanks for the reply! Ideally I'd like to be able to get around 60kms. Realistically 20-30 in the hills either pulling a trailer or more likely wearing a 60lb pack. Part of the investment into battery making is so I could make and carry a spare. Or have one solar charging while the other is in use.

I like the bbshd because I've heard its quiet and near bombproof. I'd probably want to mod it to be better but I'd still use it economically. It's more just that I've noticed the benefits and limitations of different power ranges so in want to capability especially for long or steep, rooty uphills on loose dirt or snow. That's also why I want a DH bike. The rear end stay down really well and youncam run a low PSI. Harder for the motor but big difference in climbing. I also like that I can help it up with pedaling to save some juice/extend range.

Two more reied mentioned another motor. I'm not opposed to trying something new/different but I heavily rely on previous knowledge. I can DIY OK but this is my first build. I have a 1000w hub motor far bike that ive nearly rode into the ground. So I know I need more. But don't want to pay emtb prices or get a talaria that I can't pedal.

I do some 3b printing and some welding so I can come up with a battery case that I could condifently put facing the ground if need be if there's no room inside the frame. Idnalso consider a rear rack for the battery or maybe a 2nd battery. Since it would also help keep weight over the rear if my backpack doesn't do enough of that alreasy. (I'd more likely work with pack cause a trailer would not be fun to ride off road with and over complicate things I think)

 

[ev7]

I think you should go for either @LightningRods small block or big block. Small block is a step above BBSHD, power is equivalent to a stock Surron, big block is at the 72V Surron power level.

On the site it seems to be motor only. Nothing showed up under kits. Is there info on how to manufacture the drivetrains and get this thing mounted to a bike? I figured bbshd cause its got a huge knowledge base. Proven reliability.and its apparently quiet and torquey. I would consider something more powerful.. If it checked some of those other boxes. Keeping up with talaria is very secondary moreso I don't want him waiting for me to crawl up 45* hills @ 5kph when he's doing 20 but I'm okay doing 10 krn15 and giving some pedal assistance. I'd like being able to pedal as well to assist my range and be able to ride out if I do run out of range earlier than expected.

Thanks for the reply!

 

[A-DamW]

If someone wants to help that would be awesome!

I'll be 3rd to recommend a LightningRods small block.

BBSHD would work fine too, if you don't push the limits.

 

[99t4]

Idnalso consider a rear rack for the battery or maybe a 2nd battery.

Think again about that. Especially with a FS frame. Hard to make a cantilever rack sturdy enough to counter the tail-wagging forces of that much weight hanging off the back, especially when trail riding. Best to keep weight centralized between the wheels.

 

[SlowCo]

You can hang a triangle battery pack under the downtube just above the BBSHD on a FS-DH bike frame. Just make sure the front tire doesn't hit it on full suspension compression. Mine is just a BBS02B with a 52V 21Ah pack. More modern cells will have higher capacity in the same size.

 

[E-HP]

I'll be 3rd to recommend a LightningRods small block.

BBSHD would work fine too, if you don't push the limits.

4th!!
If he wants to keep up with his friends, the BBSHD won’t cut it, even pushing past it’s limits, but if they stop, he can catch up to them.

 

[neptronix]

CYC Photon Gen 2 seems to be a very good mid drive.
More expensive but much lighter, more efficient, and more powerful in stock configuration.

BBSHD is old trusty for many people though.

 

[ev7]

Think again about that. Especially with a FS frame. Hard to make a cantilever rack sturdy enough to counter the tail-wagging forces of that much weight hanging off the back, especially when trail riding. Best to keep weight centralized between the wheels.

Good point.

 

[ev7]

CYC Photon Gen 2 seems to be a very good mid drive.
More expensive but much lighter, more efficient, and more powerful in stock configuration.

BBSHD is old trusty for many people though.

Louder and less reliable with more maintenance I heard as well. But price is also a factor for sure, I'm not opposed to maintenance. Want to it to be dependable.

 

[ev7]

4th!!
If he wants to keep up with his friends, the BBSHD won’t cut it, even pushing past it’s limits, but if they stop, he can catch up to them.

Haha yes exactly I'm going for more utility than adrenaline but without making friends wait too long.

 

[phobos]

CYC Photon Gen 2 seems to be a very good mid drive.
More expensive but much lighter, more efficient, and more powerful in stock configuration.

On paper it is more powerful indeed. There are no independent tests so far to prove it can run at 2kW for more than 5 minutes without disintegrating though. BBSHD can run at 3kW+ modified so by extension can run at the advertised 1.6kW stock for an extended period of time. I'd say it is more powerful than cyc photon gen 2 by looking at the thermal mass alone.

 

[Nix Liou]

CYC tends to rate their motors at a power level around the peak, not the continuous, while basically all other motors are rated at a continuous rating (though there's a lot of different ways to measure "continuous")

 

[neptronix]

On paper it is more powerful indeed. There are no independent tests so far to prove it can run at 2kW for more than 5 minutes without disintegrating though. BBSHD can run at 3kW+ modified so by extension can run at the advertised 1.6kW stock for an extended period of time.

Eh you're right but on a power to weight ratio it's an impressive motor for what it is.

 

[ginekolog]

I suggest giant trance 2017-2019 frame and 90 or 100mm bbshd. Battery 52v fitts inside , ground clearnance is 20cm. Works for me and my enduro rides.

 

[2old]

I'm a big fan of Bafang and have a 10+ year old BBS02 that's been operated in pretty extreme conditions without maintenance or failure. However, as above, the Talaria is a 45 mph "bike", and unless you tweak the BBSHD significantly your pals will be waiting for you IMO.

 

[E-HP]

I'm a big fan of Bafang and have a 10+ year old BBS02 that's been operated in pretty extreme conditions without maintenance or failure. However, as above, the Talaria is a 45 mph "bike", and unless you tweak the BBSHD significantly your pals will be waiting for you IMO.

Yup, can’t really match the power to weight ratio, with the huge motor advantage. If you put the motor rotors side by side, you can tell just by looking that it’s David vs Goliath as far as power and torque goes.